Explanations:

Not looked for yet. Confusion and exageration around the sighting and events reported by actress MichÃ¨le Morgan (see Paris for the same day), around the sighting by writer "M. C." (see here), and probable invention of the photograph.

The Loren Gross reference does not refer to this but to the "M. C." case and other cases in Paris at that date.

Keywords:

(These keywords are only to help queries and are not implying anything.)

Paris, photograph

Sources:

[---] indicates sources which I have not yet checked.

[---] "UFO Photographs Around the World", book by Wendelle Stevens and August Roberts, USA, 1986.